Telegraph system



`- A)e :.25f, 1928.

l R. c. MATHEs TELEGRAPH SYSTEM Filed Jan. 10, 1928 Vl Sw .ull h l\ /fm; FJ nm M. :M U RA .A WM M l my 0 n ad n V1 m 7 w3 QU JLT L| .w1 EW? L|J ma u T 1 7 T .Vw nu i i N n 3 F 111; 24| 7 r U7 IIT .Mq mz 1U? L NU; m55 AU Q ,W u AAW W UH||HMH um l 1| 1 3 -d La NN Q Q Q Q ...u m u S S ,G G :G n n .i Q t `Patented Dec. 25, 1928. l

UNITED` `STATES `IROBET C. MATHES, OE WYOMING, NEW

1,696,246 FFICE'.

PATENTo JEESEY, ASSIGNOR TO WESTERN ELECTRIC COMPANY, INCORPORATED, OF NEXV YORK, N. Y., A CORPORATION 0F NEW YORK.

TELEGRAPH SYSTEM.

Application filed January 10, 1928i Serial No. 245,647.

This invention relates to telegraph signaling systems adapted for high speed transmission.

An object of the invention is to improve the accuracy of operation of repeating or receiving systems of the type in Vwhich a ifibrating relay arrangement controlled by a rotarydistributor is employed for regenerating impulses of unit length which have been lost in transmission.

According to the present invention this object is attainedl by connecting the incoming line to a pair of condensers through a synchronously operated rot-ary distributor in such a mannerV that the two condensers are alternately charged by `successive line current impulses, the value of each charge corresponding'to the area under the line current curve for a selected fraction of a line current impulse interval. By selecting a fraction ofthe current impulse interva the effects of line distortion are minimized. While one Condenser is being charged, the other is discharging in a circuit extending through the relaying or repeating means and one of a second pair of eondensers. The condensers of the second pair which are also alternately charged, but from a local source of energy, Vare charged by means of the vibrating action of a pair of relays connected to the rotary distributor and discharged simultaneously with the first pair of condensers through the common discharge circuit, only one condenser of each pair being discharged at one time. Inasmuch as the vcharges on the condcnsers, discharging simultaneously, may beet opposite polarities, the charge having the higher .value Will control the operation ot the relaying or repeating means and ,in this manner alternating impulses of positive and negative current are furnished to opcrate the relaying or repeating means in place of the successively transmitted single unit line impulses whichu are lost by attenuation in attaining high speed transmission. i vThis invention contemplates a telegraph system inwhich a. vibrating relay arrangement is automatically maintained in synchronisn'i with the transmitting and receiving `mechanisms, or more specifically, the Jfrequency of vibration of a vibrating vrelay arrangement is under the control of a receiving distributonvwhich in turn, as in standard `multiplex printing telegraph systems, is automatically maintained in synchronism with the transmitting distributor. .A system in accordance with the invention comprises a pair of condenser-s connected directly to the line through a synchronously operated rotary distributor, a pair of vibrating relays synchronously operating with the rotary distributor and a second pair of' condens rs lconnected 'through the contacts of the vibrating relays to alocal source of battery for inserting current impulses of unit length Vto replace those which are greatly attenuated in transmission over a cable. 4 Y

The above and other objects and advan-A tages of the invention are set forth in the following description which may be more readily understood'if considered in conjunction with the accompanying drawing. The drawing illustrates the receiving apparatus at station X which is connected by a cable lOto a distant station (not shown). Eachv station isprovided with a special rotary distributor connected to the cable through a receiving `condenser ll shunted by aresistance l2 or other form ofydistortioncorrection network, the input and output circuits` of a space discharge or other type of amplifier 13 anda conductor 14. This distributor is arranged to rotate in synchronism with other distributors connected to the cable in accordance with practice well known in the art. Of the distributor at station X the receiving face only is shown and this face comprises seven ring sets 15 to 21, inclusive, shown in'part only as representing sectors A to F for sixsuccessive impulse intervals, it being required for the proper operation ot the system that the receiving face have an even number of sectors. The time intervals for the signal impulses are each broken up into three parts corresponding to the sub-sectors A1, A2, A3, B1, B2, and B3, etc. and each part shall be approximatelyone-thirdof the total length of a single time unit, although it is desirable in most cases to make the central part of each signal unit as short as compatible lWith the speed and relays whichare used in the receiving circuit. The operating functions of the A and B intervals Varecyclica-lly repeated, G interval corresponding to A, D to B etc. Brushes 22`to 28, inclusive,'are arranged to rotate in contactual engagement with ring sets l5 to steadiness of operation of the incoming signal impulses of two or 21, respectively, and in such a manner that they establishfcontacts with their respective ring' sections Within each signal interval simultaneously. Polarized relays 29 to 32, inclusive, are biased in the manner shown and are arranged to be momentarily operated by alternate currents of positive and negative polarities interspersed with Vperiods ot' no current, by the rotation ot brush 225 over ring set 16. The operating action ot these relays is such that when brush 23 picks up' positive current, the armatures thereof are actuated to their left or S contacts and when the brush picks up negative current the armatures are actuated to their right or M contacts. It follows then that the armatures of relays 9.9 and 32 are on their t5 contacts during the time intervals A, and A3. and on their M contacts during the time intervals A3, B1, B2 and :Br and that the armatures ot relays 30 and 31 are on their M contacts during intervals B1 and E: and on their S contacts during the intervals A1, A2, 151 and B3. The relays are similarly ail'ected` as the brush 23 rotates through sector pairs C and D and E and F, ctc.

Ring set 15 receives the incoming signal impulses from conductor 14 and the central portion oit each impulse impresses a charge as brush 22 rotates over ring set 15 on one or the other of two condensers 33 and 34k which are arranged to be alternately charged through the operation of relays 29 and 30. These condensers are further arranged to discharge alternately, but through the oper- ,ation of relays 31 and 32, the discharge being effected through a circuit extending through a local'arnpliier 35 and a receiving relay 36 and a second pair of condenscrs 37 and 38 during the time that brush Q6 is rotating over segments corresponding to the central parts A2, B27 etc. of the signal intervals. Relay 36 is of the unbiased polarized type and is responsive to only those charges on condensers 33 and 34, that are stored by more units length, the charges on condensers 37 and aiding in operating the relay during the intervals in 'which coi'idensers 3 3 and let arc discharging the low voltages stored therein by the incoming signals of unit lengt-l1. The operation of relay 3G closes a circuit extending from either the positive or negative pole of battery 39, depending upon the polarity of the incoming signals, to recorder 4.0.

Condensers 37 and 38 are arranged in a vibrating relay circuit comprising ring sets 2() and 21, relays 41, 42 and 113, potentiometer 45 and local battery 39, and the charges thereon are referred to herein as local charges. lt will he well to note at this point that when the incoming signals are of unit length the charge stored on either of condensers 3T and 38 will always be opposite in polarity to that stored simultaneously on either-ot the line condenscrs 3? or Iri and therefore the simultaneous discharge ol a line and a local charge in series through a common circuit, aid in operating relay 3G. But ivhen a line signal of tivo vormore units length is received the cha rge on the line condensers becomes strong and the condensers receiving the second impulse of the signal vvill be charged with a potential of the same polarity as the condenser receiving the first impulse, and therefore in accordance with the alternate arrangement of condenscrs 3T and 38 one of the latter condcnsers will rcceive a charge` troni battery 3S) which is now of the same polarity as the charge on the line y condenser, corresponding lo the second impulso oi the signal. ln the simultaneous discharge of tht-se charges of lil-:e polarity the charge on the line condenser being considerably stronger will predominate and there- 'tore hold the armature ol relay 8G in the positon in which it was last moved. telay St will thus be maintained in one position for a duration of a long signal and the polarity of the alternate charges on condenser-s 37 and 38 will remain unchanged in the in terini. y

The vibrating relay circuit is connected to the operating circuit oi relay :lo through the contacts of thc polarized relay 43 which operates simultaneously with relays 29 to 32 and therefore impulses generated in the vibrating circuit are impressed on the operating circuit ol relay iti-in synchronism with the incoming signal impulses and aid in operating thc receiving relay during those intervals in which single unit signals of alternating polarity are being received. Vibrating relays 41 and l2 are alternately operated as the brushes 2T and QS rotate over their respective ring Sets Qt) and 2l and thereby alternating on condensers 3T and titl impulse charges of a polarity corresponding to that ot the last impulse relayed to recorder by receiver relay 3G.

Before beginning with the detailed description ot the operation of the arrangement shown on the drawing it will also be well to note that the ring .sets l5 to il are concentric rings and arc, i'or the salie of clear-ness, shown on the drawing as dcvel pcd. The ring sets each consist ol` two rings, one ot which is continuousW and the other segmented, the segments being so arranged in cach ring set as to provide the proper sequence oi" operation in the receiving circuit. Ring set 15 which is connected to the lineprovides in its segmented ring three segments for each signal impulse interval and these segments are arranged so that the middle or second segments receives the signal impulse at its greatest amplitude,

the first and third segments bring left dead.

Ring 1G has its segmented ring divided into tivo segments ior each signal Intervall, one

having alength of approximately two-thirds.

i middle part of the signal impulse incoming from the line and arranged in radial alinek mont with the live or signal segments oit` ring set 15,'the long `segme: ts which have a length of approximately twice that oif the `short segments being lett dead. The short .segments of set 19 are provided to allow (voir densers 33 and 34 to alternately discharge throughvthe windings oi' relay 36, charge of one condenser being eiiected at a time when the other condens-er charged over ring setl by the nent-inco1ning impulse. The segmented ring-sof ring setslt" and 18 are similar in 'that both serve the same purpose, that is, to eilect the complete discharge offcondensers 33 and 34 be fore a second charge can be stored on either condenser. Inasmuch as the condensers 33 and 34 are alternately discharged, the discharges of each are effected in alternate sig--y nal intervals and consequently the segmented rings of ring sets 17 and 18 are arranged as shown,` so that condenser 33 effects its co1nplete discharge during` the third part of one signal interval and condenser 34 eiliects its complete discharge during the third part of the next signal interval. The segmented rings of ring sets 20 and 21 are also similar to each other in that they likewise serve the one purpose, that is, to effect the alternate i operation of relays 41 and 42 which 'control the chargeson condensers 37 and 38,. lnasmuchV as condensers 37 and 38V discharge simultaneously with the condensers 33 and 34, respectively, it is `necessary that condensers 37 and 38 bocharged in alternato signal intervals. `Therefore, the segmented arrangements of ring sets 20 and21 are each provided with a live segment in alternate signal intervals, the live segments in. one ring set being located in different signal intervals than those in the other, so that one or the other of relays 41 and 42 will be oper ated ineach signal interval.

For the purpose of describing in detail the arrangement shown on the drawing, it is sumed that the distant station is transn'iitting a message comprising one positive, two negative, one positive and one negative impulse and that the first signal `impulse is received at a time when brushes 22 to 28 are entering sector A. It is further assumed that the ksignal transmitted just preceding the above signal combination was a negative impulse being of two or more units length and that tl1erefore Vcondenser 34 contains a strong charge of negative potential and condenser 37 con-` tains a local or comparatively weak charge of positive potential, the charge on condens-v er 34 being sutiieiently .strong to operate relay 36 to its M contact when brush 26 rotates `through sector A. The lirst live segment `Vengaged byy any of the brushes is the first long one in ring set 16, which is engaged by brush L3. This segment `is connected to the positive pole of batteryV 44 and immediately upon the establishment ot the contactbe- `tween the brush and segment polarized relays 29 to 32 and 43 operate to the position shownin the dran-'ing andcondenser 33 is connected te ringoet 15 in preparation for kthe iirst incoming signal, which is of positive current. As brush 22 passes fromsubsector A,` and rotates over the segmentiin sub-sector A2 stored in condenser` 33. rotating over the segment in 'sector A2, brush a light positive charge isV While brush 22 is i 26 is rotatingover the `first short segment "i shown in ring set 19 and thus `completes gli the discharge circuit of condenser 34; The

armature oit ,relay 41is at this time in its normal position'and therefore brush 26 also completes the discharge circuit for condenser 37. The .discharges of condensers 34 and 3T aid in operating receiving relay 36 to its M Contact, thereby generating a signal oi negative current for the recorder 40 which signal is representative of thatftransmitted from the distant station just previous to the above signal combination. At` the end of subsector A2, brush 23 passesoii the long segment of ring set 16, thereby disconnecting positive battery from relays 29 to 32 and 43 and the armatures of relays 29 and 32 are actuated to their respective contacts M. j At the same time, condenser 33 having been charged by a weak impulse of positive current is disconnected `from the Vline as brush 22 disengages its associated segment in subsector AJ. VThe brushes now enter subssector A, and brush v2S electsV the operation of vibrating relay 41 which moves its armature into engagement with its right-hand contact. The armature of relay 3 6 being in engagement with its M contact causes a negative charge 'from battery 39 to be stored in condenser 33, the cliarge being regulated by potentiometer 45 to be of such 'a value as to operate relay 36 in conjunction with the weak .positive charge on `condenser 33 when both. coiidenscrs later on discharge simultaneously through the windings of' the relay. Brueh 25 in rotating throughsub-sector A3 closes a circuit extending overcontact M of relay 32, through condenser 34 to ground, which circuit effects the complete discharge ofthe heavy negative potential on condenser 34.

` As the brushes enter sub-sector Bl, relay 4l being of the `polarized biased type rcturns to normal andbrush 23 engages a segnient connected to the negative pole ot battery 44. `Relays 29 to 32 and 43 are thereupon energized, and relays 30 and 31 actuate their armatures to their respective M contacts. The brushes then proceed to suhsector Bg, whereupon brushes 22 and 2G close effective circuits, the former connectingcondenser 34 to the line over closed contact M of relay 30 and the latter connecting condenser i3 to the local amplilier 35 of relay d6 over closed contact M ot relay 3l. W'hile condenser 34 is being charged by the second incoming signal with an inipulso ot negative current, condenser 33 with its weak positive charge is discharging through the winding ot relay Relay having actuated its armature to its M contact during interval li, now allows condenser 38 to discharge its negative potential through the windings of relay 3G simultaneously with the discharge or the positive potential on condenser 32 and these charges aid in operating relay 3G to more its armature to its S contact, thereby recording a signal ot positive currenty ip recorder 40. V l' t lhe movement or the armature ot relay 5G may be determined by the direction ot the current in the discharging circuit indicatedby the arrows on the resistance 4G bridged across the input terminals otl ainplitier 35, a downward direction signilfying that the armature engages the S contact, and an upward direction signifying an engagement with the M contact. When the brushes reach the end of sub-sector BL the negative charge on condenser 34 has re ehed a higher value than the positive charge received by condenser 33 during the interval A2, because as stated above, the second signal impulse is followed by another impulse of like polarity and consequently both im pulses attain a greater amplitude than the impulse for the tiret signal which was of unit length. W'hen the brushes enter subsector BQ, the negatively charged condenser 34 is disconnected from the line. and negative battery 44 is disconnected `troni relaysl 2l) to 32 and 43, whereupon relays 30 and :il return their respective armatures to their S contacts. The return of the arma-ture ot relay 3l to its S Contact at this time connects condenser 33 to ground through brush 24 and the condenser is drained ot any residual charge. Brush 2T connects ground to the circuit extending from battery through the winding ot relay 42 which causes relay 42 to operate and close its letthand contact` thereby' establishing the circuit for impressing a .positive charge on condenser 37. When the brushes reach the end of sub-sector B3, the armature ot' relay 42, which relay is also ot the polarized biased type, returns to its normal position.

lu sub-sector C, brush 23 again connects the positive pole of battery 44- to the wind ings ot' relays 29 to 32 and 43. Relay 29 operates to connect condenser 33 to the line in preparation tor the third incoming signal. Relay 32 operates and interconnects it: armature and S contact in preparation for the discharge ot the strong negative potential on condenserll, and relay 43 operates and interconnects its armature and S contact to prepare for thc discharge Vot the local positive potential on condenser 2:37. .is the brushes proceed through subsector Gg, the line is connected through brush 22 to condenser 33 which now receives the third incoming signal or the sew ond negative charge of great amplitude. Simultaneously, brush 2G completes the die charging circuit prepared at'the armature and S contact of relay 32, so that the negative charge on condenser 34: and the posh tive charge on condenser 37 may discharge simultaneously through the windings of: relay 36, the charges again aiding, but in a direction (indicated as upward in resistance 46) to cause the operation of relay 3G to engage its M contact, thereby generating an impulse of negative current for the recorder 4.0. At the end of sub-sector C2, brush 23 disconnects relays 29 to 32 and '43 and the armatures of relays 2S) and 32 return to their M contacts. In sub-sector Cn brush 25 co1npletcs the discharge of condenser 34. Brush causes relay 4l to operate, thereby allowing condenser 38 to be charged with negative potential.

In subsector D1 negative current from battery 44 energizes relays 29 to 32 and 43 and the armatures ol relays 30, 31 and 423 are actuated to their M contacts. Condon 34 is connected to the line in preparation for the next or fourth incomingr signal aud condenser 33 connected to the ring set 15) to prepare the circuit t'or the discharge ot its negative potential. Then the brusl'ies enter sub-sector Di., brush completes thc line circuit to condenser 34, which is now charged by a weak impulse ot positive current and brush 2t, completes the discharging circuit ot condenser 33. At this time relay 42 is in normal condition and the armature and contact M of relay 433 are closed, thereby allowing condenser 38 to discharge simultaneously with condenser 33. Condenser 33 being charged negatively and to a higher value than the negative charge on condenser 23S predominatcs in the discharging circuit and the. current flows through resistance 4G in an upward direction, which causes relay 3G to more its armature to its M contact, thereby generating a signal ol' negative current for the the` recorder 4H. The brushes upon leaving sub-sector 1).. cause a deenergization of relays 2f) to 32 and 43 and the armatures of relay 30 and 8l re- At the beginning of sub-sector El, brush- 23 causes positive current from battery 44 to again energize relays 29 to 32 and 43 and the armatures of relays 29, 32 and 43 movek to their S contacts, thereby connecting condensers 33 and 34 to the ring sets 15 and 19,

respectively In subsector E2, `brush 22 causes condenser 33 tobe negatively charged by the fifth incoming signal, which being of allow a local charge of unit length is relatively Weak and Vbrusli 26 completes the discharging circuit for condensers 34 and 37. The negative charge on condenser 37 4and the weak positive charge on condenser 34 aid in operating relay 36 and the direction of current through resist ance 46 being in a downward direction causes the armature ot' the relay to engage Vits S contact to send an impulse of positive current to the recorder 40. The brushes 4then proceed'into sub-sector E3, wherein thearmatures of relays 29 and 32 return to their M contacts to disconnect condenser 33 from the line circuit, connect condenser 34 to ground and operate `relay 41 momentarily to positive potential to bestored on condenser 38.

In sub-sector F1, relays 29 to 32 and 43 are again energized by negative current from battery 44 and the armatures of relays 30, 31 and 43 are actuated to their respective M contacts, thereby connecting condensers and 34 to ring `sets 19 and 15, respectively. lVhen the brushes enter sub-sector F2, condenser34 is charged by the Vsixth incoming signal which is assumed herein to be of positive polarity in order that the fifth and last impulse of the combination selected for the purpose of describing the invention, may be ofunit length. The Weak negative charge on condenser 33 discharges simultaneously with the positive charge on condenser 38 through the winding oit relay 3G in a direction which actuates the relay armature to its M contact, thercbgi" smlding negative current from battery 3Q to the recorder 40 to record the tiith signal.. It Will be noted that the brushes have passed over six sectors of the distributor and only tive signals have been recorded. This eX- plained by the fact that the recordation of the incoming signals is effected in the intervals immediately following those in which they are received at the distributor.

In this manner signals are recorded at the receiving station inthe same Wave iorm as they were transmitted from the distant a vibrating station,a` wave form of veach recorded ysignal extending over the full length vot a signal interval, but out of phase with the in coming signal wave-by one interval due to the time constant of the receiving apparatusL It is obvious from the previous dea system in which signal impul-seshof unit length will have no appreciable effect on the receiving relay36 because of the attenscription that the presentinvention provides nation characteristic of the cable, but other signal impulses representing such unit signal impulses will be repeated or relayed from a local source into the receiving circuit by aI pair of condensers arranged to be Aalternately charged and` alternately` discharged in synchronism with the transmitting and receiving synchronous distributors. However, vwhen signal impulses of two or more units length are received, Vanother pair of condensers are alternately arrangedv to receive these signals in the form ot' a `relai tively heavy charge `and these charges are alternately discharged througlra common circuit simultaneously With the charges on the first mentioned pairof condensers and being of a higher value predominate in op erating the receiving relay. I Vhat is claimed is: y Y

l. A telegraph system comprising a line terminating in a rotary distributor, a pair of condensers arranged to bel alternately charged by line current impulses, asecond pair of condensers arranged to bealternately charged during successive line impulse intervals and relaying or repeating'means, characterized in Vthis that the condensers ot each pair are alternately discharged' through a circuit common to the members ot' eachy air, onecondenser of each pair being disc argedA simultaneously and the pre dominating l.charge of the condensers discharging at the same time controlling the operation of said relaying or repeating means.

2. A method of relaying or repeating telegraphic signals in a high speed transmission system Which consists in storing current charges corres ending in polarity to the .impulses received rom the line and balanc-4 ing such charges against other charges stored synchronously With the charges from the incoming line impulses, said other charges be-v ing etiective to operate relaying or repeat.- ing means when tie first mentioned ycharges are ineffective to operate said means.

3; A method of relaying or repeating telegraphic signals ina high speed transmission system Which consists in storing on a plurality of condensers current charges corresponding in polarity tothe `impulses received from the line and balancing such charges against other charges on a second group of condensers which are controlled by device operating synchronously with incoming line impulses, the latter charges being effective to operate said relaying "or repeating means when they are higher in value than lthe charges furnished by the incoming line impulses.

4. A method of relaying or repeating telegraphie signals in a high'speed transmission system which consists in storing on a pair of condenser-s current charges corresponding 'in polarity to theimpulses received from the line and balancing such charges against charges on a second pair of eondensers which are controlled by a pair of vibrating relays operating synchronously with the incoming line impulses, the latter charges being eective to operate said relaying or repeatlng means when they are higher in value than the charges furnished by the incoming line impulses.

5. In a telegraph system, an incoming line, a rotary distributor arranged to receive signal currentV impulses from said lin-e, means for storing impulses incoming from said line, a local source of energy, other means for storing electrical impulses received from said local source of energy in synehronism with the incoming line impulses, a circuit extending through said distributor for discharging both of said means simultaneously, and ineans in said circuit arrangedvto be controlled by the higher current value of the impulses discharging simultaneously.

6. In a telegraph system, an incoming line, a rotary distributor arranged to receive signal current impulses from said line, a plurality ofeondensers arranged to be charged alternately through said distributor in response to signal impulses, alocal source of energy, a second group of 4condensers arranged to be alternately charged from said local source of energy, al circuit common to both ot said groups of condensers for discharging a condenser of each group simultaneously, and relaying or repeating means in said discharging circuit arranged to be cont-rolled by the )redominating charge of the condensers discharging at the same time.

7. In a telegraph system, an incoming line, a rotary distributor arranged to receive signal current impulses from said line, a pair ot' condensers ar 'anged to be charged alter-l nately through said distributor 1n response to signal impulses, a local source of energy, a second pair of condensers arranged to be alternately charged from said local source of energy, a circuit common to both of said pairs ofcondenscrs for discharging a condenser of each pair simultaneously,iand relaying or repeating means in said discharging circuit arranged to be controlled bythe predominating charge of the condenscrs discharging atv the same time.

8. In a telegraph system, an incoming line, a rotary distributor for receiving signal current impulses from said line, a pair of eondensers arranged to be alternately charged in response to signal impulses, a pair of vibrating relays connected to `said distributor and arranged to operate alternately during successive signal intervals, a local source ot energy, a second pair ot (fondent-:ers arranged to be alternately charged by said local source of energy by the operation of said vibrating relays, and a circuit comprising relaying or repeating means for simultaneously effecting a discharge of a condenser of each of said pairs, the predominating charge on the eondensers discharging at the same time controlling the operation of said relaying or repeating means.

vIn AWitness wlereof, I hereunto subscribe my name this -Jtth day of January, 1928.

ROBERT C. MATHES. 

